Wave Mechanics Question 86

Question: An underwater sonar source operating at a frequency of 60 KHz directs its beam towards the surface. If the velocity of sound in air is 330 m/s, the wavelength and frequency of waves in air are:

[DPMT 2004]

Options:

A) 5.5 mm, 60 KHz

B) 330 m, 60 KHz

C) 5.5 mm, 20 KHz

D) 5.5 mm, 80 KHz

Show Answer

Answer:

Correct Answer: A

Solution:

Frequency of waves remains same, i.e. 60 Hz and wavelength $ \lambda =\frac{v}{n}=\frac{330}{60\times 10^{3}} $ = 5.5 mm.